System and method for supplying water to an oven

ABSTRACT

An oven includes a housing forming a cooking compartment defining an interior of the oven. A water supply line extends through the housing to position an end behind a fan within the cooking compartment. The fan is arranged within the cooking compartment near the water supply line to create a low pressure area about the end of the water supply line to draw water through the water supply line and into the fan.

CROSS REFERENCE TO RELATED APPLICATIONS

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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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BACKGROUND OF THE INVENTION

The present invention relates generally to ovens using moving air and/orsteam to cook food and, more particularly, to a system and method forhandling water in combination ovens.

Many ovens include the ability to cook food using steam. For example,combination ovens provide the ability to cook foods using steam, hot-airconvection, or both steam and convection. This combination of convectionheating with steam provides a system where food can be properly cookedsignificantly faster than with traditional ovens or even convectionovens alone. As a result, combination ovens have become a vital asset incommercial cooking environments that need to cook food quickly and,often, in large quantities.

Combination ovens employ a motor driven fan to circulate air within acooking chamber past electrical heating elements or gas heat exchangetubes to perform the convection functionality. To produce steam withinthe cooking chamber, a pressurized water line injects water into thecooking chamber, for example onto a rotating cup at the center of thefan, near the heating elements to disperse and vaporize the water. Asystem of this type is described in U.S. Pat. 6,188,045 issued Feb. 13,2001, entitled: “Combination Oven With Three-Stage Water Atomizer”,assigned to the assignee of the present invention and herebyincorporated by reference. In this regard, combination ovens requireaccess to both electricity and pressurized water supply lines, such asmunicipal water supply lines.

Internal plumbing within the combination oven receives pressurized waterfrom the plumbing of the kitchen and delivers it into the cookingchamber of the combination oven. As such, the internal plumbing issubjected to at least a portion of the heat generated within the cookingchamber. While modem plumbing techniques are designed to withstandvariations in temperatures, the internal plumbing of combination ovensmust be able to tolerate a temperature range extending from roomtemperature to several hundred degrees Fahrenheit (F). Furthermore, theinternal plumbing must be able to tolerate this entire temperature rangesimultaneously during cooking periods because the plumbing fixturesarranged to interface with the kitchen plumbing are surrounded by roomtemperature conditions, while plumbing fixtures extending into thecooking compartment are surrounded by several hundred degree steam.

As such, a substantial cost of producing a combination oven is incurredin creating an internal plumbing system that is suited to theseoperating conditions. For example, considerable engineering design andmanufacturing expertise is utilized to create internal plumbing systemsfor combination ovens that have a minimal number of joints and sealsbecause such interfaces are negatively impacted by wide temperaturevariations.

Additionally, when including or incorporating a combination oven into akitchen, the cost of purchasing the combination oven as well as the costof providing the resources necessary to operating the combination oven(i.e. electricity and pressurized water connections) must be considered.In some cases, the cost of these resources may significantly impact thedecision to include a combination oven within a kitchen.

The cost and complexity of installing a combination oven is at least onereason that combination ovens have only been widely adopted in largecommercial kitchens and have not gained significant adoption in smallercommercial kitchens and consumer or home kitchens. In particular, it iswidely recognized that plumbing costs account for a substantial amountof kitchen building expenses. This is generally true in both newconstruction, but can be particularly true when remodeling. As such, thedecision to incorporate a combination oven into a kitchen, particularlya previously completed kitchen, may be relatively costly and outside ofthe budget for small commercial and/or residential kitchens.

Accordingly, it would be desirable to have a system and method to reducethe costs associated with ovens employing steam and, in particular,plumbing costs associated with such ovens. More specifically, it wouldbe desirable to have a system and method for reducing the manufacturingcosts associated with internal plumbing systems of ovens employing steamas well as for reducing the installation plumbing costs associated withincorporating such an oven into a kitchen.

SUMMARY OF THE INVENTION

The present invention overcomes the aforementioned drawbacks byproviding a system and method for providing an oven with water withoutthe need for extensive internal plumbing or pressurized water supplies.Specifically, the present invention includes a passive water supplysystem that is caused to draw water from an external reservoir inresponse to a low pressure area created by rotation of a fan within acooking chamber of the oven. In this regard, the fan creates the forcenecessary to draw water into the oven, atomizes the water by drawing itinto the rotating blades of the fan, and circulates the atomized wateralong with the air in the cooking compartment.

In accordance with one aspect of the invention, an oven is disclosedthat includes a housing defining an interior cooking compartment forholding food at an elevated temperature. A fan is positioned adjacent toa wall of the housing to circulate air and water within the cookingcompartment during a cooking process. Additionally, the fan provides anair flow region between the fan and the wall. A water supply lineextends from an exterior of the housing through the wall at a pointbehind the fan to deliver water to the air flow region between the fanand the wall to be dispersed by the fan before passing into the cookingcompartment. Accordingly, the water supply line length in the cookingcompartment may be minimized.

In accordance with another aspect of the invention, an oven is disclosedthat includes a housing forming a cooking compartment defining aninterior of the oven. A water supply line extends through the housing toposition an end of the water supply line within the cooking compartment.A fan is arranged within the cooking compartment near the end of thewater supply line to create a low pressure area at the end of the watersupply line to draw water into the cooking compartment from an externalreservoir.

In accordance with yet another aspect of the invention, a method ofoperating an oven is disclosed that includes energizing a heatingelement configured to heat an enclosed cooking compartment of the oven.The method also includes rotating a fan to circulate air within thecooking compartment. Accordingly, a low pressure area is created thatsurrounds a water supply passage extending from a reservoir of waterinto the cooking compartment and that draws the water through the watersupply passage into the cooking compartment to generate steam from thewater.

Various other features of the present invention will be made apparentfrom the following detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an oven having a water supply system inaccordance with the present invention;

FIG. 2 is a perspective, partially exploded view of the water supplysystem of FIG. 1; and

FIG. 3 is vertical cross-sectional view of the water supply system asassembled and engaged with the housing of the oven of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, an oven 10, for example, a combination oven,includes a housing 11 having an oven door 12 that provides access intoan inner cooking compartment 14 created within an interior of thehousing 11. The oven 10 also includes a user interface 16 through whichdesired operational parameters or cooking processes may be entered by auser, an electrical connection 18 to provide electricity to the oven 10,and, as will be described, a water supply system 20 through which wateris delivered to the oven 10 in order to generate the steam necessary toeffectuate a combination convection cooking and steam cooking process.

In operation, a user places food within the cooking compartment 14 viaoven door 12 and enters the desired cooking parameters through the userinterface 16. Responsive thereto, electricity is drawn from theelectrical connection 18 and water is drawn from the water supply system20 to generate the heat and steam necessary to carry out the desiredcooking process.

Referring now to FIG. 2, the water supply system 20 generally includes areservoir 22, a water supply line 24, and a fan 26. The fan 26 includesa first circular plate 28 having a plurality of circumferentially spacedholes 30 formed along its periphery and a second parallel circular plate32 of equal dimension spaced from the first plate 28 along a commonrotational axis 33. A plurality of cupped blades 34 extends between theplates 28 and 32, joining the plates 28 and 32 at their peripheries justoutside the holes 30. As the fan 26 rotates about the axis 33, thecupped blades 34 move with their concave faces forward to create aradially outward flow of air 35.

The plates 28, 32 also include central holes 36, 38 designed to becoaxially aligned along the axis 33 to receive a drive shaft 40connected to a motor 42. In this regard, the motor 42 can rotate thedrive shaft 40 to thereby rotate the fan 26.

The motor 42 is positioned outside the housing 11 with only the driveshaft 40 passing through a vertical wall of the housing 11 protectingthe motor from high temperatures within the cooking compartment 14.According to one embodiment, the fan 26 is positioned within a fewinches of the wall 11.

When the fan 26 is mounted on the drive shaft 40, a first end 44 of thewater supply line 24 may pass through the wall of the housing 11 behindthe fan 26 so that the first end 44 of the water supply line 24 islocated proximate to the first plate 28 of the fan 26 having theplurality of holes 30 formed therein. In this way, only a short lengthof the water supply line 24 needs to extend into the cooking compartment14 and no pipe fitting such as elbows and the like are positioned withinthe cooking compartment 14. It is contemplated that the first end 44 ofthe water supply line 24 may be near and generally parallel to the motordrive shaft 40. A second end 46 of the water supply line 24 is submergedin a supply of water 48 held in the reservoir 22.

Referring now to FIG. 3, when the water supply system 20 is assembled,such that the first end 44 of the water supply line 24 extends from theexterior through the housing 11 of the oven 10 and into the cookingcompartment 14, the fan 26 is positioned on the drive shaft 40 andwithin the housing 11 of the oven 10. As such, when the fan 26 isrotated during a cooking process, air is drawn by the blades 34 radiallyalong the wall and away from the housing 11, which creates a lowpressure area 50 between the fan 26 and the housing 11 of the oven 10.As previously described, the first end 44 of the water supply line isarranged proximate to the first plate 28 of the fan 26 and, as such, isarranged within the low pressure area 50 between the fan 26 and thehousing 11 of the oven 10.

Referring now to FIGS. 2 and 3, when the first end 44 of the watersupply line 24 is subjected to the low pressure area 50, water 48 isdrawn from the reservoir 22 through the second end 46 of the watersupply line toward the first end 44 of the water supply line 44. In thisregard, water is pulled from the reservoir 22 into the cookingcompartment 14 of the oven 10 by the low pressure area 50. Furthermore,water is pulled by the fan 26 through the holes 30 formed in the firstplate 28. The water impinges upon the blades 34 extending from thesecond plate 32, is atomized due to this contact, and is circulated intoa convection flow as generally indicated by path 52. When entering theconvection flow 52, the atomized water is subjected to the heatgenerated by a heating element 54 that substantially encircles the fan26. In this regard, the atomized water is quickly vaporized and heatedto the desired steam temperature.

Therefore, a system and method for delivering water into a oven isprovided without the need for plumbing connections to pressurized watersupplies, such as municipal water supplies. Furthermore, by arrangingthe convection fan 26 of the oven 10 within close proximity of a wall 11of the cooking chamber 14 and arranging one end 44 of the water supplyline 24 within that wall 11 near the fan 26, a low pressure area 50 canbe created that will be capable of drawing water from the externalreservoir 22 into the cooking compartment 14.

Therefore, the above-described system and method advantageously removesthe need for connections to pressurized water sources. However, it iscontemplated that a pump, though not required, may be included to drawthe water from a remotely located reservoir and deliver the water to aposition adequate to then be drawn by the low pressure area into thecooking compartment of the oven, for example a combination oven.

By removing the need for connections to pressurized water sources, theinternal plumbing systems required for receiving pressurized water anddelivering it into the cooking compartment is advantageously removed andmanufacturing costs are reduced. Furthermore, by utilizing asignificantly simplified and cost effective water supply system, acombination oven can be created that is easily incorporated into akitchen. That is, referring again to FIG. 1, the oven 10 may be easilyincorporated into a kitchen area without plumbing connections. In thisregard, the oven 10 may be easily retrofitted into a kitchen and mayeven be advantageously located on a countertop 56 or other work surfacebecause special accommodations for the oven 10 need not be made.

Therefore, a system and method is provided for supplying water to anoven without the need for pressurized water supply lines and associatedplumbing systems. Rather, a passive water supply system is used thatdraws water from an external reservoir in response to the creation of alow pressure area within a cooking chamber of the oven generated byrotation of a fan. In this regard, the fan creates the force necessaryto draw water into the oven, atomizes the water by drawing it into therotating blades of the fan, and circulates the atomized water along withthe air in the cooking compartment. Hence, a highly efficient and costeffective combination oven can be created.

It is specifically intended that the present invention not be limited tothe embodiments and illustrations contained herein, but include modifiedforms of those embodiments including portions of the embodiments andcombinations of elements of different embodiments as come within thescope of the following claims.

1. An oven comprising: a housing defining an interior cookingcompartment for holding food at an elevated temperature; a fanpositioned adjacent to a wall of the housing to circulate air and waterwithin the cooking compartment during a cooking process, the fanproviding an air flow region between the fan and the wall; a watersupply line extending from an exterior of the housing through the wallat a point behind the fan to deliver water to the air flow regionbetween the fan and the wall to be dispersed by the fan before passinginto the cooking compartment; an unpressurized reservoir of water influid communication with the water supply line; and wherein the fancreates a low pressure area in the air flow region that causes the watersupply line to draw water from the unpressurized reservoir into theinterior cooking compartment.
 2. The oven of claim 1 further comprisinga motor external to the cooking compartment having a drive shaftextending through the wall to support the fan.
 3. The oven of claim 2wherein the air flow region is an area of radial air flow about thedrive shaft between the fan and the wall.
 4. The oven of claim 1 whereinthe fan creates a low pressure area in the air flow region with respectto air pressure outside the housing.
 5. (canceled)
 6. The oven of claim1 wherein the fan comprises: a first element providing a dispersingsurface receiving and dispersing water from the water supply line; and asecond element providing a plurality of blades to establish an airflow.7. The oven of claim 6 wherein the first element is a plate parallel tothe wall having the blades attached thereto and extending away from thewall and, wherein the plate further includes a plurality of holesallowing passage of water through the plate to be further dispersed bythe blades.
 8. The oven of claim 1 further comprising a heating elementdisposed within the cooking compartment and arranged proximate to andsubstantially encircling the fan to vaporize water drawn into thecooking compartment by the fan.
 9. The oven of claim 1 wherein the ovenis a combination oven.
 10. An oven comprising: a housing forming acooking compartment defining an interior of the oven; an reservoir ofliquid arranged externally from the cooking compartment; a water supplyline having a first end in communication with the reservoir andextending above the first end, through the housing, and to a second endarranged within the cooking compartment; and a fan arranged within thecooking compartment near the second end of the water supply line tocreate a low pressure area between the housing and the fan and about thesecond end of the water supply line to draw water into the cookingcompartment from the reservoir.
 11. The oven of claim 10 wherein the fanis further configured to atomize the water and circulate air and theatomized water within the cooking compartment during a cooking process.12. The oven of claim 11 further comprising a heating element configuredto heat the atomized water to create steam within the cookingcompartment.
 13. The oven of claim 12 wherein the heating element isconfigured to substantially encircle the fan.
 14. The oven of claim 10wherein the low pressure area is an area of radial air flow between thefan and the housing.
 15. The oven of claim 10 wherein the fan comprises:a first element providing a dispersing surface receiving and dispersingwater from the water supply line; and a second element providing aplurality of blades to establish an airflow.
 16. The oven of claim 15wherein the first element is a plate parallel to a wall of the housinghaving the blades attached thereto and extending away from the wall and,wherein the plate further includes a plurality of holes allowing passageof water through the plate to be further dispersed by the blades. 17.The oven of claim 10 wherein the oven is a combination oven.
 18. Amethod of operating an oven comprising: energizing a heating elementconfigured to heat an enclosed cooking compartment of the oven; rotatinga fan to circulate air within the cooking compartment and create a lowpressure area surrounding a water supply passage that extends from anunpressurized reservoir of water located below the fan and into thecooking compartment; wherein the low pressure area is sufficient to drawthe water up from the unpressurized reservoir of water through the watersupply passage and into the cooking compartment to generate steam fromthe water.
 19. The method of claim 18 further comprising atomizing thewater drawn into the cooking compartment by drawing it into the rotatingfan and vaporizing the atomized water by subjecting the atomized waterto the energized heating element to generate the steam.
 20. The oven ofclaim 10 wherein the reservoir is unpressurized.